Hello All, The same silvery features are visible on many of the 'Berduc' stones (and on many other falls); I believe that they are the result of the melting of troilite present in the meteorite. This would create iron sulfide, albeit iron sulfide that looks rather different from the unaltered material we're used to seeing on the cut surfaces of stones and irons. Regards, Jason
On Mon, Mar 23, 2009 at 2:38 AM, Jeff Kuyken <i...@meteorites.com.au> wrote: > G'day John & all, > > That's certainly an interesting theory but I don't know either if that is > possible or not. I hope someone studying West will have the opportunity to > study this feature. I was having a think about this the other day > too. A couple of ideas I had were: > > 1) Possibly a reaction between something in the fusion crust (iron > component... magnetite?) and localised soil and/or vegetation. (i.e. > staining by acidic compounds?) This is just a thought which I don't know > virtually nothing about. > > 2) The second is obviously more like something that happened during passage > through the atmosphere. For example the silver sheen on magnetite crystals > is due to high luster on the crystal faces (reflectivness). In this case > could it be due to an abrasive ablation effect? > > I bet there are MANY theories on this feature and I'd certainly be > interested to hear some. > > Cheers, > > Jeff > > > ----- Original Message ----- From: "John Gwilliam" <j...@cox.net> > To: <mccart...@blackbearddata.com>; <meteorite-list@meteoritecentral.com> > Sent: Monday, March 23, 2009 11:13 AM > Subject: Re: [meteorite-list] Silver stuff on the West? > > >> Here's an idea about the "silver" blotches on some of the West meteorites. >> Could it be pure nickel? I don't know if it's possible for metallic >> particles in meteorites to consist of mostly nickel. Are all iron/nickel >> blebs a homogeneous mix of the two metals? The color of this "silver" >> blotching looks a lot like matte nickel plating that is often found on >> firearms and some plumbing fixtures. >> >> Just a thought. >> >> Best, >> >> John >> >> At 10:19 PM 3/19/2009, McCartney Taylor wrote: >>> >>> I have found another specimen with a pronounced silver 'line' >>> http://outofabluesky.com/images/stories/stoneymeteorites/west15-1.jpg >>> >>> I really don't know what to make of it. In this new piece, its like its a >>> silver blob that melted and oozed out of the tiny gash in the stone. I'm >>> disinclined now to a post fall chemical reaction. Do take note of the >>> oxidation effect the rain had on the stone. >>> >>> There is another specimen with silver 'blotches' on this page, the 29.5g >>> piece. >>> >>> http://outofabluesky.com/index.php?option=com_jportfolio&cat=4&project=46&Itemid=58 >>> >>> Any good theories out there? >>> >>> -mt >>> >>> >>> ______________________________________________ >>> http://www.meteoritecentral.com >>> Meteorite-list mailing list >>> Meteorite-list@meteoritecentral.com >>> http://six.pairlist.net/mailman/listinfo/meteorite-list >> >> John Gwilliam >> >> Too many people were born on third base >> and go through life thinking they hit a triple. >> ______________________________________________ >> http://www.meteoritecentral.com >> Meteorite-list mailing list >> Meteorite-list@meteoritecentral.com >> http://six.pairlist.net/mailman/listinfo/meteorite-list >> >> > > ______________________________________________ > http://www.meteoritecentral.com > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list